High-speed drill.



L. J. CAMPBELL.

HIGH SPEED DRILL.

APPLICATION FILED 001216, 1911.

Paterlted DEXLQA, 1912.

ml! 1 ap MT/VESSAIS: QQ? W tached to the shan NIT D STATES LEON .1. current, on CHICAGO, ILLINOIS,

HIGH-SPEED DRILL.

Specification of Letters Patent.

Patented De. 24,1912.

Application filed October 16, 1911. Serial No. 654,897. v

To all whom it may concern:

Be it known that I, LEON J CAMPBELL, a citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in High* Speed Drllls, of

which the following is a complete specification.

The main objects of this invention are to provide a high speed drill having a detachable bit; to provide a high speed drill in which the bitor cutting portion is relatively short as compared with the shank and is formed of a much harder metal than the shank; to provide a high speed drill in which the shank is adapted to have various sizes of bits attached thereto, so that a number of sizes of holes may be drilled with one shank by simply changing the bits; to provide improved means for attaching the bit to the shank; and to provide an improved high speed drill in which the drill may be quickly and easily detached from or at-' Y The invention consists of the matters hereinafter described in the specification and In the drawings: Figure 1 is a fragmentary side elevation of a high speed drill embodied in this invention. Fig. 2 is an end elevation of the cutting end of the drill. Fig. 3 is a side elevation of, thejoint end of the shank. Fig. 4 is a View of the. joint end of the shank taken at right angles to that shown in Fig. 3. Fig. 5 is anend elevation of the joint end of the shank. Fig. 6 is a top plan view of the bit show'n in Fig. 1. Fig. 7 is a side elevation of the bit shown in Fig. 1. Fig. 8- is a side elevationv of the bit taken at right angles to the view shown in Fig. 7. Figs. 9 and 10 are side elevations of the locking pin or key for the bit. Fig. 11'

is a fragmentary side elevation of a modified form of the drill. Fig. 12 is a side elevation of the joint end of the shank shown in Fig. 11. Fig. 1?) is a side elevation of the bit shown in Fig. 11. Fig. 14 is a bottom plan view of the bit shown in Fig. 11. 7

Referring first to the construction shown in Figs. 1 to 10, inclusive, the shank 1 of the drill is shown as a twist drill and is formed of relatively soft, tough steel. The lower orjoint end 2. of the shank is provided with a central longitudinally directed diametricallydis'posed slot 3, which divides the end into jaws 4 and 5. The outer face 6 of each jaw is in alinemcnt with the side of the shank and the bearing or contact face 7 of each jaw is beveled or inclined in a plane-at right angles to the plane of the slot 3 so as to give endwise tapered form to the jaw, while the inner-faces 8 of the jaws, or those formed by the slot 3, are parallel with the central longitudinal axis of the shank. The jaws 4 and 5 have their beveled faces 7 oppositely inclined and laterally o-fl'set from each other both atthe bases and outer ends of the jaws so that the lines indicating the beveled faces, as seen in the side view of the shank, Fig. 4,

cross or intersect each other and present a V.-shaped opening 9 between the outer endsed, but is fiat and of less torsion than the shank, and may be of a width or diameter equal to or greater than the diameter of the shank 1. The jointend of the bit is pro vided with oppositely beveled jaws 12'and 13, which have their front faces 14 beveledcomplementally with the faces 7 'of the shank and are adapted to seat on said faces .7 when the bit is in place. At the lower end of each face 14- is an abrupt or squared shoulder 15 having a cross sectional shape or area equal to that of the abutting end of the jaws 4 and 5'. When the bit is in opera tive position the shoulder does not quite contact with the end of the jaw of the shank. Said shoulders are formed by the upper ends of downwardly and laterally extending ribs 16 which terminate in'a point at the corners 17 of the bit. The inner faces 18 of said ribs'are curved, to carry the shaving or chips into the flutes. 19 of the shank. The inner edges ofthe jaws 12 and 13 are connected by. a web 20 adapted to enter the groove 3 of the shank when the bit is in place, and an aperture or key seat .21 extends through the inner edges of the'jaws. and through the web. When the bit is placed on the shank the key seat 21 partially registers with the. keyseats 10 and a drift pin or key 22 is adapted to extend thrbughsaid seats, and when forced into place tends to draw the bit onto the shank and rigidly lock it in place.

In the construction shown in Figs. 11 to 14, inclusive,- the bit 23 has the same degree of torsion or twist as has the shank 24. The

lapping jaws 25 and 26 respectively, and the jaws '25 of the bit are connected at their inner edges by a. web 27 which projects beond the ends of the jaws and enters a slot 28 in the shank. The jaws 9.5 and 26 on each side of the drill are provided with key seats 29 formed in the inclined or beveled faces thereof.(see Fig. 11), one half of each seat being in each of the jaws 25 and 26, and keys 30 are adapted to be secured in said seats to hold the bit firmly in place. 1

The operation is as follows: A bit of the same or greater diameter than that of the shank is placed on the shank and the drift pin or key is inserted in the key seats, and when pounded or forced into said seats it acts to draw the jaws of the bit firmly up into the jaws of the shank. When it is desired to replace the bit with one of a different size it is only necessary to knock out the pin.and the bit may be removed from the shank.

The jaws of the shank and bit are so arranged that, when in operation, the jaws of the shank push against the jaws of the bit, thereby avoiding any tendency to open the joint.

Obviously many details of the construction shown may bevaried or omitted without departing from the scope of the claims.

I claim:

1. A drill, comprising two members, a shank and a removable bit therefor, each member having endwise extending jaws overlapping those of the other member, the jaws of each member being located at opposite sides of a plane passing through the central longitudlnal axis of the drill and having their hearing or contact faces oppositely inclined to give endwise tapered form to said jaws, and fastening means for looking said members together, actingto draw the awe of the bit and shank longitudinally toward each other.

2. A drill, comprising two members, a shank and a removable bit therefor, each member having a pair of endwise extending jaws overla ping those of the other member, the jaws 0 each member being located at opposite sides. of a plane passlng through the central longitudinal axis of the drill and having their bearing or contact faces inclined or beveled to give endwise tapered form to said jaws, and fastening means for locking said members together embracing endwise facing, transverse surfaces on the said members, and a locking member engaging said surfaces and acting to draw the jaws of the bit and shank longitudinally toward each other.

3. A drill, comprising two members, a

shank and a re ovable bit therefor, each member having a pair of endwise extending jaws overlapping those of the other member, the jaws of each member bein located at opposite sides of a plane passing through the central longitudinal axis of the drill and having their hearing or contact faces inclined or beveled to give endwise tapered form to said jaws, and fastening means for locking said members together, consisting of oppositely disposed transverse key seats in the jaws of the bit and shank, and a key adapted to engage said seats.

4. A drill, comprising two members, a shank and a removable bit therefor, each member having a pair of endwise extending jaws overlapping those of the other member, the jaws of each member being located at opposite sides of a plane passing through the central longitudinal axis of the drill and having their bearing or contact faces inclined or beveled, to give endwise tapered form-to said jaws, said members having transverse key seats formed in the inclined or beveled surfaces of its jaws, and a key adapted to engage said key seats.

In testimony whereof I have hereuntosubscribed my name in the presence of two I witnesses.

LEON J. CAMPBELL. Witnesses:

JAs. T. HEALY, N. W. WITHENBURY. 

